1. Field of the Invention
The invention relates to a display device. More particularly, the invention relates to a sensing display device.
2. Description of Related Art
In this information society, people increasingly depend on electronic products. The electronic products such as all-in-one personal computers (AIO PCs), tablet personal computers (tablet PCs), personal digital assistants (PDAs) or smart phones are widely used in daily life. In order to achieve purposes of convenience, compact size and humanity, conventional input devices of many information products such as keyboards and mice have been replaced by touch panels, and a sensing display device or a touch-screen simultaneously having a touch control function and a display function becomes one of most popular product.
Generally, the sensing display device includes a display panel and a sensing element, wherein the sensing element can be built in the display panel or externally attached to the display panel. The sensing element generally includes a plurality of sensor unit with fixed coordinate positions, wherein each of the sensor units has one or a plurality of electrodes. When a user approaches or touches the sensor unit with his or her finger, capacitance between the electrodes is changed, and a signal indicating such a change is transmitted to a controller, so as to calculate the coordinate of the touched location. Thereby, a display image on the display panel can be changed according to the user's operation.
In the conventional sensing display device or touch-screen, to ensure transmittance of the sensing element, a transparent conductive material can be used to fabricate the electrodes. However, since the transparent conductive material has drawbacks of high resistance and high price, metal mesh is suggested to be used for fabricating the electrodes. Since the metal mesh is composed of grids formed by extremely fine metal wires, the mesh-pattern electrode not only maintains and increases the transmittance, but also has relatively small resistance, so that a better sensitivity is achieved.
However, since the mesh-pattern of the electrodes and a pixel array in the display panel are both arranged periodically, the mesh-pattern electrodes and the pixel array may cause the display a visual Moiré issue. Therefore, the sensing display device may have problems of image blur and poor visual quality.